The differentiation of mammalian corneal epithelial cells will be studied in cell culture. The specific problems to be investigated are the following: 1. Molecular mechanism of the intrinsic modulation of the differentiated state of rabbit cornea epithelial cells, with emphasis on the two corneal-epithelial-specific proteins which are not found in epidermal cells. 2. Biochemical differentiation of cultured human corneal epithelial cells, with emphasis on the structure and biogenesis of their keratin proteins. 3. The pathophysiology of the epithelial abnormalities in a number of ophthalmologic disorders. Cell culture techniques and subsequent biochemical analysis will be used.